1. Field of the Invention
The present invention relates to a lubricating device for a linear guideway, and more particularly to a lubricating device for a linear guideway whose oil-containing member can maintain an all-the-time effective contact with the rail even after wear and tear.
2. Description of the Prior Art
With the development of science and technology, and the improvement of the precision feeding system, linear guideway and technology thereof have become a most important part of many precision mechanisms. Various types of linear mechanisms have been and are being widely used in different fields. Although the linear guideway technology is developing fast, still there are some problems of the linear products that need to be improved. Many efforts have been made by the related industry to effectively improve the quality of linear guideway, in particularly, those high precision mechanisms (such as wafer processing equipment and CNC Computer Numeric Control instruments) that need to run stably and silently. Therefore, there are still some blind spots in the existing linear mechanisms that need to be exploited and erased.
Most of the existing linear guideways are provided at both sides of the slide block thereof with oil tanks in which is received an oil-containing sponge. The oil-containing sponge will wear out after long time of use, so that a clearance will appear between the sponge and the rail of the linear guideway, and it will prevent the lubricating oil from reaching the linear guideway. Therefore, many linear products have been developed to solve this problem, they generally includes the following three types:
First, arranging a spring in the oil tanks and using it to push the oil-containing sponge against the rail, but the shortcoming is too complicated in structure and not easy for assembly. In addition, the spring will become loose with the wear of the oil-containing sponge and also because of the elastic fatigue of the spring itself (such as the device of U.S. Pat. No. 5,547,285).
Second, arranging a reverse U-shaped elastic piece in the oil tanks and using it to push the oil-containing sponge against the rail, but the shortcoming is, like the previous one, that the spring will become loose with the wear of the oil-containing sponge and also because of the elastic fatigue of the spring itself (such as the device of U.S. Pat. No. 6,672,764).
Third, arranging an elastic rubber in the oil tanks and using it to push the oil-containing sponge against the rail, but it still has the same shortcoming as the previous two.
The present invention has arisen to mitigate and/or obviate the afore-described disadvantages.